Main routes generally still existed in 1976.
Peter Pan Bus Lines - operated 1933-present
Original route: Boston-Springfield-Northampton
Trailways member (Peter Pan Trailways) 1992-2006
Peter Pan Bus Lines remains in existence
Bus companies generally listed in the July 1942 Russell's Guide or the 1952 Mass Transportation's Directory, and their predecessor and successor companies. This list is somewhat arbitrary and provides a general overview.
The Arrow Line - operated until 2000
Original route: Albany NY-Hartford-Providence RI
Grey Goose Line - operated until 1946
Original route: Providence RI-New London
Flying Eagle Whiteway Lines - operated until 1946
Original route: Hartford-Danbury-New York City
Newburgh-Danbury Bus Line - operated 1937-1944 (to Flying Eagle Whiteway Lines/above)
Original route: Danbury CT-Newburgh NY
Prior to 1937 was Danbury Interurban Bus Co.
Intercity Coach Co. - operated until 1958
Original route: Bridgeport-Waterbury/Danbury
Shuttle Bus Line - operated until 1951
Original route: Winsted-Poughkeepsie NY
1948-1951 was Lakeland Transportation Co.